// Copyright 2007-2008 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef V8_DISASM_H_
#define V8_DISASM_H_

#include "src/vector.h"

namespace disasm {

typedef unsigned char byte;

// Interface and default implementation for converting addresses and
// register-numbers to text.  The default implementation is machine
// specific.
class V8_EXPORT_PRIVATE NameConverter {
public:
    virtual ~NameConverter() = default;
    virtual const char* NameOfCPURegister(int reg) const;
    virtual const char* NameOfByteCPURegister(int reg) const;
    virtual const char* NameOfXMMRegister(int reg) const;
    virtual const char* NameOfAddress(byte* addr) const;
    virtual const char* NameOfConstant(byte* addr) const;
    virtual const char* NameInCode(byte* addr) const;

    // Given a root-register-relative offset, returns either a name or nullptr if
    // none is found.
    // TODO(jgruber,v8:7989): This is a temporary solution until we can preserve
    // code comments through snapshotting.
    virtual const char* RootRelativeName(int offset) const { UNREACHABLE(); }

protected:
    v8::internal::EmbeddedVector<char, 128> tmp_buffer_;
};

// A generic Disassembler interface
class Disassembler {
public:
    enum UnimplementedOpcodeAction : int8_t {
        kContinueOnUnimplementedOpcode,
        kAbortOnUnimplementedOpcode
    };

    // Caller deallocates converter.
    explicit Disassembler(const NameConverter& converter,
        UnimplementedOpcodeAction unimplemented_opcode_action = kAbortOnUnimplementedOpcode)
        : converter_(converter)
        , unimplemented_opcode_action_(unimplemented_opcode_action)
    {
    }

    UnimplementedOpcodeAction unimplemented_opcode_action() const
    {
        return unimplemented_opcode_action_;
    }

    // Writes one disassembled instruction into 'buffer' (0-terminated).
    // Returns the length of the disassembled machine instruction in bytes.
    V8_EXPORT_PRIVATE int InstructionDecode(v8::internal::Vector<char> buffer,
        byte* instruction);

    // Returns -1 if instruction does not mark the beginning of a constant pool,
    // or the number of entries in the constant pool beginning here.
    int ConstantPoolSizeAt(byte* instruction);

    // Write disassembly into specified file 'f' using specified NameConverter
    // (see constructor).
    V8_EXPORT_PRIVATE static void Disassemble(
        FILE* f, byte* begin, byte* end,
        UnimplementedOpcodeAction unimplemented_action = kAbortOnUnimplementedOpcode);

private:
    const NameConverter& converter_;
    const UnimplementedOpcodeAction unimplemented_opcode_action_;

    DISALLOW_IMPLICIT_CONSTRUCTORS(Disassembler);
};

} // namespace disasm

#endif // V8_DISASM_H_
